There was a point when I began to wonder whether my columns on immigration might violate the government’s proposed new racial vilification offence.

This new criminal offence, which would have carried a maximum penalty of five years in prison, was to be defined by three criteria. It’s worth setting these criteria out:

• the person engages in conduct in a public place
• the person engages in the conduct intending to either: promote or incite hatred of another person or persons because of their race, colour or national ethnic origin; or disseminate ideas of superiority over or hatred of another person or group of persons because of their race, colour or national ethnic origin
• the conduct would, in all the circumstances, cause a reasonable person who is the target, or a member of the target group, to be intimidated, to fear harassment or violence, or to fear for their safety.

The most worrying aspects of these provisions were, firstly, the use of the verb ‘promote’ and, secondly, the reasonable person test. I’m still scratching my head about just who is this reasonable person. Most of us think of ourselves as reasonable people.  Ditto Harold Shipman, Bernie Madoff, Al Capone, Erin Patterson and the list goes on.

Of course, it is never my intention in any of my writing to promote, let alone, incite hatred. Hatred is such a strong term. No doubt, this principle applies to all Speccie writers.

At the same time, my aim is to contribute to vigorous debate, to state the facts and to outline solid research findings. With migrants being the major source of additional supply to the labour market, it’s impossible to ignore the topic. The broader economic impact of immigration must also be considered – for example, on housing affordability and consumer spending.

What I thought I would do is list some of what I regard as settled findings on immigration – I refrain from using the term ‘consensus’ as this has been rendered meaningless in the context of climate change discussion. And then consider whether that mythical reasonable person could feel vilified.

• Immigration increases the size of the economy, but its impact on per capita GDP is unclear.
• Relatively young migrants with good English language skills and recognised qualifications add to national income but many other migrants do not.
• The net economic effect of immigration is slightly positive, depending on the composition of the migrant intake, or zero/slightly negative.
• In the short term, immigration reduces productivity growth by diluting the capital stock.

That’s probably all OK, but there are certain groups and individuals who might prefer that I kept quiet on the topic when research results point to zero or negative effects.

But what about the fiscal effects of migrants? According to official Treasury estimates, it’s only skilled migrants that generate a positive lifetime fiscal impact on the federal budget. Secondary migrants that accompany their skilled migrant partners, by contrast, don’t generate any lifetime fiscal benefits at all: expenditure equals revenue.

But here’s the kicker finding: those migrants who enter under humanitarian visas – refugees – have an average lifetime fiscal negative impact of greater than $300,000 per migrant. In other words, bringing in refugees is a very costly undertaking and it’s one reason that the annual intake has been kept quite small, at least until recently.

Now these are not my figures, but you can see how some ‘reasonable’ person might take offence at the relaying of them.

A ‘reasonable’ person probably really likes the never-ending stream of propaganda emanating from the Special Broadcasting Service about how well refugees are doing.  A business set up by a refugee or a refugee football team established in a disadvantaged part of a big city – they’re the stories a ‘reasonable’ person prefers.

Immigration is known to have distributional consequences: there are winners and losers. The winners include the owners of capital – that is businesses, including property developers – and workers with skills complementary to the incoming migrants. For those workers who compete with incoming migrants, it’s a different story. Job opportunities can become limited and relative wages suffer.

This finding has been well established in the US, with George Borjas of the Harvard Kennedy School one of the leading researchers in the field. Interestingly, Borjas has found himself at the centre of recurring intellectual controversies, notwithstanding the fact that Borjas himself was born in Cuba.

The potential impact of immigration on the incentives for employers to train local workers is obvious. Why bother putting resources into training when workers with adequate skills can simply be imported. We see this especially in aged care and childcare.

But here’s the thing: the research indicates that where migrants take up employment in large numbers in particular industries, the locals tend to vacate the field.  This is particularly the case for lower-paid, semi-skilled work.

It’s hard to know whether I would have been pinged under the racial vilification provision for my commentary. If some person or group of persons decided to pursue me, at the very least, I would have been caught up in months, if not years, of very upsetting and expensive litigation. Just ask Andrew Bolt about his experience with Section 18C. Working for known publications could have helped – as opposed to commenting on social media, say – but who knows?

Can I also make the point that shutting down my writing on immigration would do absolutely nothing to reduce the incidence of antisemitism in this country? Just saying.

This brings me to my beef about the Liberal party voting in favour of the group hate speech provisions, passed recently by parliament. What were those members who cast a Yes vote thinking?

Sure, we need to ban groups like Hizb ut-Tahrir, a known terrorist group that is banned in several countries. This group should have been named in the legislation. And stricter vetting of visa applicants from Muslim countries simply makes sense.

But you only have to look at the actual words in the Act to realise how loopy – and dangerous – the whole thing is. Take this doozy: ‘the minister must be satisfied that banning the group is reasonably necessary to protect the Australian community from social, economic, psychological and physical harm’. What does that sentence even mean? Economic harm? Who is to judge that?

Any assurances that groups that legitimately engage in public debate, including promotion of free speech, will never be targeted are meaningless down the track. If the government of the day doesn’t like what a particular group is saying, there is always the option of trotting out some ‘reasonable person’ and it will be on for one and all.

Notwithstanding the latter-day worship of Robert Menzies, he was just wrong to try to ban the Communist party. Taking it to a referendum was appropriate and the punters got it right. Eventually, the Communist party imploded, destroyed by its own internal contradictions plus some toxic individuals.

Banning is not an option any government should contemplate save in the case of violent terrorist groups.